Guide insert for PCI connector receptacle

ABSTRACT

Electronic equipment includes a frame having a wall and connectors attached to the wall of the frame. A main board has a connection edge at which it is provided with connectors for engaging the connectors that are attached to the wall of the frame when the main board is advanced relative to the frame along a connection axis. An edge connector receptacle is attached to the wall of the frame and defines a slot perpendicular to the connection axis and to the connection edge of the main board. An auxiliary board is attached to the main board and is oriented perpendicular to the main board and parallel to the connection axis. The auxiliary board has a connection edge perpendicular to the connection edge of the main board and positioned to enter the slot of the edge connector receptacle concurrently with engagement of the connectors at the connection edge of the main board with the connectors attached to the wall of the frame.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] Certain subject matter disclosed in this application is relatedto subject matter disclosed in copending application Ser. No. ______filed ______ (Attorney Docket No. ADC 2122), the entire disclosure ofwhich is hereby incorporated by reference herein for all purposes.

BACKGROUND OF THE INVENTION

[0002] This invention relates to a circuit board structure withincreased edge connection capacity.

[0003] It is common practice to make electrical connections betweencircuitry on a printed circuit board and a power supply or an externalsignal source or signal destination by mechanically engaging aconnection edge of the board with a mating receptacle and simultaneouslyestablishing electrically conductive connections between an electricallyconductive structure at the connection edge of the board and acomplementary electrically conductive structure incorporated in thereceptacle and including contacts that are electrically connected to thepower supply or to the signal source or destination, as the case may be.In one conventional case, the receptacle and electrically conductivestructure incorporated therein is known as a card edge connector and theconductive structure at the connection edge of the circuit board is aprinted pattern of conductive strips. It is possible to provideconnections at a density as high as 38 pins per inch of circuit boardedge with this type of connection scheme.

[0004] It is not always convenient or desirable to employ a card edgeconnector for connecting circuitry on a printed circuit board withcircuitry off the circuit board, and in some cases it may be necessaryor desirable to employ coaxial connectors, such as the connectors thatare commonly known as BNC connectors. For example, in one applicationwhere BNC receptacles are provided in a backplane assembly of a mountingframe and it is necessary to provide electrical connection between theBNC receptacles and circuitry on a circuit board that slides into theframe, it has been found desirable to provide BNC receptacles along theconnection edge of the circuit board and to implement the BNC receptaclein the backplane assembly with the female portion of a male/female BNCfeed through. When the circuit board is installed in the frame, areceptacle on the connection edge of the board engages the male portionof the feed through.

[0005] When BNC receptacles are used in this manner, the minimumcenter-to-center spacing of the receptacles is about 0.625 inches andaccordingly the maximum density of signal paths that can be providedalong the connection edge of the circuit board is much less than in thecase of the other conventional scheme mentioned above. If in order tomaximize the number of signal paths, the maximum number of BNCreceptacles are mounted to the circuit board at its connection edge,there is little space for other connections, for example for power linesand control signals.

SUMMARY OF THE INVENTION

[0006] In accordance with a first aspect of the invention there isprovided electronic equipment comprising a frame including a wall andconnectors attached to the wall of the frame, a main board having aconnection edge at which it is provided with connectors for engaging theconnectors that are attached to the wall of the frame when the mainboard is advanced relative to the frame along a connection axis, an edgeconnector receptacle attached to the wall of the frame and defining aslot perpendicular to the connection axis and to the connection edge ofthe main board, and an auxiliary board attached to the main board andoriented perpendicular to the main board and parallel to the connectionaxis and having a connection edge perpendicular to the connection edgeof the main board, the auxiliary board being positioned to enter theslot of the edge connector receptacle concurrently with engagement ofthe connectors at the connection edge of the main board with theconnectors attached to the wall of the frame.

[0007] In accordance with a second aspect of the invention there isprovided electronic equipment comprising a frame including a wall andconnectors attached to the wall of the frame, a main board having aconnection edge at which it is provided with connectors for engaging theconnectors that are attached to the wall of the frame when the mainboard is advanced relative to the frame along a connection axis, firstand second edge connector receptacles attached to the wall of the frameand each defining a slot perpendicular to the connection axis and to theconnection edge of the main board, the connectors that are attached tothe frame being between the first and second edge connector receptacles,and first and second auxiliary boards attached to the main board andeach oriented perpendicular to the main board and parallel to theconnection axis and having a connection edge perpendicular to theconnection edge of the main board, the first and second auxiliary boardsbeing positioned to enter the slots of the first and second edgeconnector receptacles respectively, concurrently with engagement of theconnectors at the connection edge of the main board with the connectorsattached to the wall of the frame.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] For a better understanding of the invention, and to show how thesame may be carried into effect, reference will now be made, by way ofexample, to the accompanying drawings, in which

[0009]FIG. 1 is a partial perspective view of an item of electronicequipment in accordance with the present invention and illustrates acircuit board assembly including a main board and two auxiliary boards,

[0010]FIG. 2 is an enlarged perspective view of a detail of the circuitboard assembly at one end of its connection edge,

[0011]FIG. 3 is a partially exploded enlarged perspective view of adetail of the circuit board assembly at the other end of the connectionedge, and

[0012]FIG. 4 is a side elevation of the detail shown in FIG. 3.

DETAILED DESCRIPTION

[0013]FIG. 1 illustrates a frame having two opposite side walls 10 (onlyone of which is shown) each provided with five horizontal guide channels14 for receiving respective longitudinal edges of printed circuit boards18 (only one of which is shown). Each circuit board 18 is part of acircuit board assembly 20 including the circuit board 18 (the maincircuit board) and two auxiliary circuit boards 22. The frame has a rearwall or bulkhead 26 formed with five rows of circular holes 28. Amale/female BNC feed through 30 is mounted in each hole 28 with the maleportion of the feed through presented towards the interior of the frameand the female portion presented towards the exterior, for receiving aBNC plug attached to a cable.

[0014] Several BNC receptacles 34 are attached to the main circuit board18 on the upper side thereof. Each BNC receptacle has a signal lead 36which is connected through conductor traces (not shown) of the circuitboard to at least one electronic component on the circuit board. Whenthe circuit board assembly 20 is inserted in the frame, the BNCreceptacles 34 of the main circuit board engage respective feed throughs30 on the bulkhead, providing a uniform characteristic impedance pathfrom the circuit board to the female portion of the feed through.

[0015] Two PCI card edge connector receptacles 38A, 38B are firmlyattached to the bulkhead 26. The PCI receptacles are vertically orientedand are positioned so that the BNC feed throughs 30 are between the twoPCI receptacles 38. As is conventional, each PCI receptacle 38 includesa housing 40 which is made of electrically insulating material anddefines a slot 44 for receiving a connection edge of a circuit board.Sixty contacts (not shown) are mounted in the housing and arranged inone group of 11 contacts and one group of 49 contacts spaced apart by analignment feature of the housing.

[0016] The two auxiliary circuit boards 22A, 22B are attached to themain circuit board 18 adjacent the longitudinal edges respectively. Eachauxiliary circuit board 22 is perpendicular to the main board andextends parallel to the longitudinal edges and has a connection edgethat extends beyond the connection edge of the main board approximatelyas far as the BNC receptacles. The auxiliary board is provided adjacentits connection edge with contact strips 48 of width and spacing forengagement with the contacts of a PCI receptacle. The contact strips areelectrically connected to connector runs on the main board throughconductive leads 52 that are soldered both to the auxiliary board and tothe main board and thus serve to stabilize the auxiliary board relativeto the main board. Further, the main board is formed with a notch 56into which a projection 58 of the auxiliary board extends so that themain board supports the auxiliary board against movement in thedirection of the arrow 60.

[0017] The auxiliary boards 22A, 22B are positioned relative to the mainboard 18 and the PCI receptacles 38A, 38B are positioned relative to theguide channels 14 so that when the circuit board assembly 20 is placedin the frame, with the edges of the main board 18 in the channels 14,the BNC receptacles 34 on the main board are aligned with the feedthroughs 30 in one row of holes 28 and the connection edges of theauxiliary boards 22A, 22B are aligned with the slots of the PCIreceptacles 38A, 38B respectively. When the circuit board assembly ispushed home to the rear of the frame, the BNC receptacles 34 engage thefeed throughs 30 and the connection edges of the auxiliary boards enterthe slots of the PCI receptacles. Electrical contact is made between thecontact strips of the auxiliary board 22A and nine of the contacts ofthe PCI receptacle 38A. The auxiliary board 22B engages the PCIreceptacle 38B in analogous manner. Consequently, the auxiliary boardsand the mating PCI receptacles provide edge connection capacity for 18additional connections to the main board, and may be used to providecontrol signals and power to the electronic components on the mainboard.

[0018] The guide channels 14 are positioned so that the alignmentfeatures of the housing 40 do not obstruct the auxiliary boards. Whenfive circuit board assemblies 20 are installed in the frame, each withtwo auxiliary boards 22A, 22B received in the slots of the PCIreceptacles 38A, 38B respectively, one auxiliary board 22A, for example,makes connection to 9 of the 11 contacts in the smaller group in thereceptacle 38A and the other four auxiliary boards 22A make connectionwith 36 of the 49 contacts in the larger group in the receptacle 38A, asexplained in greater detail in copending application Ser. No. ______(Atty. Docket ADC 2122).

[0019] Whether the auxiliary boards 22 engage the PCI receptacles 38before, simultaneously with, or after the BNC receptacles 34 engage theBNC feed throughs 30 is determined by the relative position of theconnection edge of the auxiliary board and the BNC receptacles 34 anddepends on the electrical requirements of the equipment.

[0020] It will be appreciated that the invention is not restricted tothe particular embodiment that has been described, and that variationsmay be made therein without departing from the scope of the invention asdefined in the appended claims and equivalents thereof. Unless thecontext indicates otherwise, a reference in a claim to the number ofinstances of an element, be it a reference to one instance or more thanone instance, requires at least the stated number of instances of theelement but is not intended to exclude from the scope of the claim astructure or method having more instances of that element than stated.

1. Electronic equipment comprising: a frame including a wall andconnectors attached to the wall of the frame, a main board having aconnection edge at which it is provided with connectors for engaging theconnectors that are attached to the wall of the frame when the mainboard is advanced relative to the frame along a connection axis, an edgeconnector receptacle attached to the wall of the frame and defining aslot perpendicular to the connection axis and to the connection edge ofthe main board, and an auxiliary board attached to the main board andoriented perpendicular to the main board and parallel to the connectionaxis and having a connection edge perpendicular to the connection edgeof the main board, the auxiliary board being positioned to enter theslot of the edge connector receptacle concurrently with engagement ofthe connectors at the connection edge of the main board with theconnectors attached to the wall of the frame.
 2. Electronic equipmentaccording to claim 1, wherein the connectors at the connection edge ofthe main board are BNC receptacles and the connectors attached to thewall of the frame are BNC feed throughs.
 3. Electronic equipmentaccording to claim 1, wherein the main board has longitudinal edgesperpendicular to the connection edge thereof and the frame includeslongitudinal guides for receiving the longitudinal edges of the mainboard and guiding movement of the main board relative to the frame alongthe connection axis.
 4. Electronic equipment according to claim 1,comprising multiple main boards each having a connection edge at whichit is provided with connectors for engaging connectors that are attachedto the wall of the frame when the main board is advanced relative to theframe along the connection axis, and an auxiliary board attached to eachmain board, the auxiliary boards being substantially coplanar, andwherein the edge connector receptacle has a slot of sufficient length toreceive the connection edges of all the auxiliary boards.
 5. Electronicequipment comprising: a frame including a wall and connectors attachedto the wall of the frame, a main board having a connection edge at whichit is provided with connectors for engaging the connectors that areattached to the wall of the frame when the main board is advancedrelative to the frame along a connection axis, first and second edgeconnector receptacles attached to the wall of the frame and eachdefining a slot perpendicular to the connection axis and to theconnection edge of the main board, the connectors that are attached tothe frame being between the first and second edge connector receptacles,and first and second auxiliary boards attached to the main board andeach oriented perpendicular to the main board and parallel to theconnection axis and having a connection edge perpendicular to theconnection edge of the main board, the first and second auxiliary boardsbeing positioned to enter the slots of the first and second edgeconnector receptacles respectively, concurrently with engagement of theconnectors at the connection edge of the main board with the connectorsattached to the wall of the frame.
 6. Electronic equipment according toclaim 5, wherein the connectors of the main board are between the twoauxiliary boards.
 7. Electronic equipment according to claim 5, whereinthe connectors at the connection edge of the main board are BNCreceptacles and the connectors attached to the wall of the frame are BNCfeed throughs.